ORDWAY, Colo. (CBS4) – The suspect in the murder of a state prison guard is a convicted kidnapper and sex offender.

Sgt. Mary K. Ricard, 55, was killed and Sgt. Lori Gann, another state employee, was seriously injured on Monday’s attack at the Arkansas Valley Correctional Facility in Ordway.

Sources close to the case told CBS4 that the inmate believed to be involved in the incident has now been moved to the Colorado State Penitentiary in Canon City, the state’s highest security prison.

The man is already serving a 35 years to life sentence for the kidnapping and rape of a 14-year-old girl from a bus stop in Colorado Springs 10 years ago.

On Monday the Department of Corrections reported that the disturbance happened in a prison kitchen and involved a knife.

Gann was hospitalized in serious condition after the attack.

The prison was placed on lockdown as an investigation began.

“We have a family in mourning. Our D.O.C. family is in mourning, but we still have a job to do and we will do that job with integrity and professionalism,” Corrections spokeswoman Alison Morgan said on Monday.

The inmate under investigation pleaded guilty in 2004 to kidnapping of the teenager from the bus stop and then forcing her into a car and assaulting her before the girl got free and ran.

He was an Army deserter from Fort Carson.

Ricard joined the Department of Corrections in 2003 and previously worked in